1. Field of the Invention
The present invention relates to a structure of a lens drive apparatus which moves each of a plurality of movable lenses included in a photographing optical system in an optical axis direction using voice coil motor mechanisms in a lens barrel of an image pickup apparatus.
2. Description of the Related Art
Conventionally, photographing apparatuses, for example image pickup apparatuses such as digital cameras and video cameras, have been generally put into practical use and widely spread, which are provided with image display apparatuses such as liquid crystal display (LCD) apparatuses that sequentially convert optical images formed by photographing optical systems into image signals using photoelectric conversion devices, or the like, record resulting image signals in recording media as image data in a predetermined format and reproduce and display the image data recorded in the recording media as images.
Such an image pickup apparatus includes a lens barrel which is configured to have a photographing optical system comprised of a plurality of optical lenses, or the like, a plurality of holding members for respectively holding the respective optical lenses, and a lens drive apparatus, or the like for moving movable lens holding members which are part of the plurality of holding members, forward and backward in an optical axis direction. As a structure of the lens barrel, there is, for example, a structure in which the movable lens holding member moves forward and backward in the optical axis direction along a pair of shaft members (a guide shaft and an anti-rotation shaft) arranged in parallel to the optical axis.
In regard to the lens driving apparatuses applied to the lens barrels of the conventional image pickup apparatuses, in recent years, various lens drive apparatuses which employ voice coil motors (VCM) as driving mechanisms have been proposed in, for example, Japanese Patent Application Laid-Open Publication No. 2013-37042. Use of a voice coil motor mechanism as a driving mechanism of a lens drive apparatus advantageously contributes to higher-speed movement of a movable lens holding member.